Improvement in screw-drivers



C. LAW.

Screw-Drivers.

No. \39,`069. Parentedlviay 20,1873` UNITED STATES PATENT FFICE. 'l

CHARLES LAW, OFPITTSTON, PENNSYLVANIA.

IMPROVEMENT IN SCREW-DRIVERS.

Specification forming part of Letters Patent No. 139,069, dated May 20, 1873; application led April 30, 1873.

To all whom it may concern:

Be it known that I, CHARLES LAW, of Pittston, in the county of Luzerne and State of' Pennsylvania, have invented certain new and useful Improvements in Screw-Drivers;

.and I do hereby declare that the following is a full, clear, and exact description thereof, that will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawing and to the letters of reference marked thereon, which form a part of this specilication.

My invention consists of making screwdrivers with self-adjusting bits or ends to their blades, whereby the range of their use may be greatly increased and the bit or swinging end adjust itself in the slot of the screw notwithstanding a variation in the blade.

In order to ena-ble others to make screwdrivers according to my invention, I will proceed to describe and explain the construction ot' the same, referring to the accompanying drawing, in which- Figure l is a perspective view of that portion of the blade of a screw-driver in which my invention is applied, A being the swinging end of the blade; C, in dotted lines, shows the position which it will adjust itselfwithin the limits of a semicircle. Fig. 2 shows a central transverse section of the end of the blade to which the swinging end is attached, and D is the slot within which the swinging end is pivoted by the means of the screw E.

Fig. 3 is the swinging end alone, and Fig. 4 isl a transverse section thereof. Fig. 5 is a modication of the swinging end. Fig. 6 is a handle with the receptacle for the bits.

It will be observed that one (w) wall of the slot is somewhat thicker than the other; this is so in order to give the screw a firm hold and equalize the strain on both walls of the slot.

In practice it is frequently necessary to drive and take out screws in places that are not accessible to an ordinary straight screwdriver without the self-adjusting end. It is an obvious economy of time and expense to have a single tool suitable for use under varidriver having a self-adjusting or swingingv end or bit pivoted to the blade, substantially as shown and described.

In testimony that I claim the foregoing I have hereunto set my hand this 28th day of' April, 1873.

Witnesses:

C. S. STARK, F. C. MosIER.

oHAnLEs LAW. 

